At a press conference on the Lower East Side in Manhattan, NYC Mayoral hopeful Bill Thompson gets the endorsement of the Uniformed Firefighters Association. (July 9, 2013) Photo Credit: Nancy Borowick

The Uniformed Firefighters Association Tuesday rolled a billboard on a flatbed truck to its news conference at a Lower East Side firehouse to show what it was willing to do for and spend on its candidate for mayor.

"Bill Thompson for Mayor," the billboard read. "Endorsed by New York's Bravest."

Steve Cassidy, president of the 8,200-member UFA, would not say how much his union planned in independent expenditures for Thompson, but stated, "We're going to do what we think is required to communicate to people around the city of New York that we strongly support Bill Thompson."

Thompson's endorsement Tuesday by the union, which backed him against Mayor Michael Bloomberg four years ago, was the latest in a list of labor support for the Democratic former comptroller that includes the influential United Federation of Teachers.

About two dozen firefighters stood with Cassidy, who said his group chose Thompson for his "temperament, experience, the ability to work across lines and get things done. We had an administration for 12 years that said, 'You're going to do it my way.' "

Asked about the union's endorsement of Thompson rival Anthony Weiner during the 2005 mayoral race, Cassidy said, "2005 was a long, long, long time ago. Plus, he quit on us. New York City firefighters don't quit."

Municipal unions have been divided in the mayoral race. Another Thompson opponent, City Council Speaker Christine Quinn, in February received the endorsement of the Uniformed Fire Officers Association.

Quinn Tuesday accepted endorsements from four City Council members -- Stephen Levin, Michael Nelson, James Gennaro and Mark Weprin.